GetMenuDefaultItem

// USER32.dll
#include <windows.h>

DWORD GetMenuDefaultItem(
    HMENU hMenu,
    DWORD fByPos,
    GET_MENU_DEFAULT_ITEM_FLAGS gmdiFlags
);

<DllImport("USER32.dll", SetLastError:=True, ExactSpelling:=True)>
Public Shared Function GetMenuDefaultItem(
    hMenu As IntPtr,   ' HMENU
    fByPos As UInteger,   ' DWORD
    gmdiFlags As UInteger   ' GET_MENU_DEFAULT_ITEM_FLAGS
) As UInteger
End Function

' hMenu : HMENU
' fByPos : DWORD
' gmdiFlags : GET_MENU_DEFAULT_ITEM_FLAGS
Declare PtrSafe Function GetMenuDefaultItem Lib "user32" ( _
    ByVal hMenu As LongPtr, _
    ByVal fByPos As Long, _
    ByVal gmdiFlags As Long) As Long
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

GetMenuDefaultItem = ctypes.windll.user32.GetMenuDefaultItem
GetMenuDefaultItem.restype = wintypes.DWORD
GetMenuDefaultItem.argtypes = [
    wintypes.HANDLE,  # hMenu : HMENU
    wintypes.DWORD,  # fByPos : DWORD
    wintypes.DWORD,  # gmdiFlags : GET_MENU_DEFAULT_ITEM_FLAGS
]
# GetLastError: use ctypes.GetLastError() (or ctypes.WinDLL(use_last_error=True))

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('USER32.dll')
GetMenuDefaultItem = Fiddle::Function.new(
  lib['GetMenuDefaultItem'],
  [
    Fiddle::TYPE_VOIDP,  # hMenu : HMENU
    -Fiddle::TYPE_INT,  # fByPos : DWORD
    -Fiddle::TYPE_INT,  # gmdiFlags : GET_MENU_DEFAULT_ITEM_FLAGS
  ],
  -Fiddle::TYPE_INT)

#[link(name = "user32")]
extern "system" {
    fn GetMenuDefaultItem(
        hMenu: *mut core::ffi::c_void,  // HMENU
        fByPos: u32,  // DWORD
        gmdiFlags: u32  // GET_MENU_DEFAULT_ITEM_FLAGS
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("USER32.dll", SetLastError = true)]
public static extern uint GetMenuDefaultItem(IntPtr hMenu, uint fByPos, uint gmdiFlags);
"@
$api = Add-Type -MemberDefinition $sig -Name 'USER32_GetMenuDefaultItem' -Namespace Win32 -PassThru
# $api::GetMenuDefaultItem(hMenu, fByPos, gmdiFlags)

#uselib "USER32.dll"
#func global GetMenuDefaultItem "GetMenuDefaultItem" sptr, sptr, sptr
; GetMenuDefaultItem hMenu, fByPos, gmdiFlags   ; 戻り値は stat
; hMenu : HMENU -> "sptr"
; fByPos : DWORD -> "sptr"
; gmdiFlags : GET_MENU_DEFAULT_ITEM_FLAGS -> "sptr"
; ※HSP3.7は #func のため戻り値はシステム変数 stat に格納されます。

#uselib "USER32.dll"
#cfunc global GetMenuDefaultItem "GetMenuDefaultItem" sptr, int, int
; res = GetMenuDefaultItem(hMenu, fByPos, gmdiFlags)
; hMenu : HMENU -> "sptr"
; fByPos : DWORD -> "int"
; gmdiFlags : GET_MENU_DEFAULT_ITEM_FLAGS -> "int"

; DWORD GetMenuDefaultItem(HMENU hMenu, DWORD fByPos, GET_MENU_DEFAULT_ITEM_FLAGS gmdiFlags)
#uselib "USER32.dll"
#cfunc global GetMenuDefaultItem "GetMenuDefaultItem" intptr, int, int
; res = GetMenuDefaultItem(hMenu, fByPos, gmdiFlags)
; hMenu : HMENU -> "intptr"
; fByPos : DWORD -> "int"
; gmdiFlags : GET_MENU_DEFAULT_ITEM_FLAGS -> "int"

import (
	"golang.org/x/sys/windows"
	"unsafe"
)

var (
	user32 = windows.NewLazySystemDLL("USER32.dll")
	procGetMenuDefaultItem = user32.NewProc("GetMenuDefaultItem")
)

// hMenu (HMENU), fByPos (DWORD), gmdiFlags (GET_MENU_DEFAULT_ITEM_FLAGS)
r1, _, err := procGetMenuDefaultItem.Call(
	uintptr(hMenu),
	uintptr(fByPos),
	uintptr(gmdiFlags),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // DWORD

function GetMenuDefaultItem(
  hMenu: THandle;   // HMENU
  fByPos: DWORD;   // DWORD
  gmdiFlags: DWORD   // GET_MENU_DEFAULT_ITEM_FLAGS
): DWORD; stdcall;
  external 'USER32.dll' name 'GetMenuDefaultItem';

result := DllCall("USER32\GetMenuDefaultItem"
    , "Ptr", hMenu   ; HMENU
    , "UInt", fByPos   ; DWORD
    , "UInt", gmdiFlags   ; GET_MENU_DEFAULT_ITEM_FLAGS
    , "UInt")   ; return: DWORD

●GetMenuDefaultItem(hMenu, fByPos, gmdiFlags) = DLL("USER32.dll", "dword GetMenuDefaultItem(void*, dword, dword)")
# 呼び出し: GetMenuDefaultItem(hMenu, fByPos, gmdiFlags)
# hMenu : HMENU -> "void*"
# fByPos : DWORD -> "dword"
# gmdiFlags : GET_MENU_DEFAULT_ITEM_FLAGS -> "dword"
# なでしこ1は32bit・ANSI(Shift_JIS)。文字列=char*(ANSI)、ポインタ/ハンドル=void*(4byte)。